Plural set time switch



June l1, 1935. R| D, SMlTH 2,004,137

PLURAL` SET TIME SWITCH Filed NOV. 25, 1931 3 Sheets-Sheet 2 5 Sheets-Sheet 3 Filed Nov. 25, 19`3l Patented June 11, 1935 UNITED STATES PATENT OFFICE 15 Claims.

This invention relates to improved means for enclosing and constructing the parts of a time switch generally similar to that described in my co-pending application Serial No. 504,532 led 5 December 24, 1930, and particularly concerns an improved arrangement of the parts thereof whereby no parts appear in front of the clock face other than the usualform of hour and minute hands and whereby the setting of the position of certain circuit making and breaking parts of the switch may be accomplished by easily manipulatedmeans .while the complete switch is enclosed within a casing containing a glass window to expose the clock face and those parts of the switch 5. which determine the time setting of its contacts.

Other objects are hereinafter stated.

In the accompanying drawings, therefore, I have s'ou'ght to facilitate a comparison cf the present improvements with the structure dis- ;0- closedin my co-pending application by using corresponding reference characters to designate certain of the parts, and in which drawings,-

Fig. 1 is a view, practically double the preferred actual size, and taken in section on a plane passing through the center of the clockwork and electric switch parts to show in section certain of the housing and time setting means with which the present improvements are concerned.

Fig. 2 is an outside front view, approximately half the preferred size, of one form of my completely housed and glassed-in combined clock and time switch.

Fig. 3 is a side view looking from the left at Fig. 2. l

Fig. 4 shows a cross section of the main case taken on `the horizontal plane 4 4 in Fig. 2, other parts being shown un-sectioned.

Fig. 5 is a view similar toFig. 2 showing a modified form of the means for setting the time determining position of certain of the switch parts.

Fig. 6 is a sectional view of the same kind and on the same scale as Fig. 1 showing in detail the construction of those parts which comprise the modification in Fig. 5. y

Fig. '7 shows a preferred form of the adjustable, insulating disc which is traversed by the rotatable switch contact finger, actual size.

Fig. 8 is an edgewise view looking down upon Fig. '7.

Fig. 9 shows a preferred form of the adjustable conductive disc which is traversed by the rotatable switch contact ilnger, actual size.

Fig. 10 is an edgewise .View looking down upon Fig. 9.

Fig. 11 is a partial sectionjshown on an enlarged scale taken on the plane II-H in Fig, 12.

Fig. 12 shows an assembly of the insulative and conductive discs of Figs. '7 to 9 inclusive with their retaining hub bushing and relatively positioned so 00 that a completely conductive track is presented to the contact wiper of the switch, Fig. 12 being a rear View of the parts or a View looking downward in Fig. 1.

Fig. 13 is a section taken through the plane I3-l3 in Fig. 12 'looking in the direction of the arrows and showing the contact finger in two positions of its travel.

Fig. 14 shows the same assembly of parts as Fig. 12 and viewed in the same direction but with the insulative and conductive discs so relatively positioned that a completely insulative track is presented to the contact finger of the switch.

Fig. l5 is a section taken through the plane I5-i5 in Fig. 14 looking in the direction of the arrows showing the contact finger in two positions of its travel.

Fig. 16, shows the same assembly of insulative and conductive discs as Figs. 12 and 14 together with portions of the enclosing shells by which the relative and absolute positions of said discs may be shifted to determine the time of automatic switch actions, the discs being so positioned that approximately for six hours the current would be made and for the remaining six hours the current would be broken.

Fig. 17 is a partial section taken on the plane I 'l-I'i looking from the left at Fig. 16 showing the contact nger in two positions respectively before and after it has broken contact.

Fig. 18 is a partial section taken on the plane I8-I8 in Fig. 16 looking from the right and showing the contact finger in two positions respectively before and after it has made the circuit.

Fig. 19 is a rear View of the casing drawn to a scale intermediate the sizes of Fig. 1 and Fig. 2 or approximately the preferred actual size showing the timing movement and electric switch parts omitted more clearly to illustrate a modication of the means by which the time setting of the conductive and insulative discs of Figs. 12, 14 and 16 may be accomplished.

Fig. 20 is a sectional view looking down upon the plane 20--20 in Fig. 19 and showing the time switch assembled in the casing.

Fig. 2l is a fragmentary sectional view taken upon the plane 2 I-Zl in Fig. 19 looking in the direction of the arrows.

Fig. 22 shows a modification of the setting wheels in the lower right hand corner of the casing of Fig. 19.

In Figs. 2, 3 and 5 there is shown a decorative form of clock case 50 which may be molded from insulating material, completely open at the back, and containing in its front wall the circular aperture 5I surrounded by a formation of the molded material of which the casing may be made, affording the bead 52 outside the casing and the recess 53 inside the casing both said bead and recess being circular and shown in enlarged sectional detail'in Figs. land 6. I may conveniently utilize the aperture 5I for mounting in rotatable relationship herein two thin metal shells 54 and 55 respectively, the former projecting inwardly of the aperture 5I andthe latter projecting outwardly and suitably formed to accommodate and retain the circular crystal or glass window 56 by means of an interior clamp ring 51. As shown in Fig. l the shells 54 and 55 may have rollthreaded engagement with each otherwhereby they are relatively and independently turnable and the shell 54 may have secured rigidly to it an outer mounting ring 58 having the flanged portion 59 adapted to seat in the casing recess 53 and be retained therein by any suitable and preferably removable backingr fixture indicated in the drawings` at 60. The inner shell 54 may also carry an annular disc 6I of insulating material preferably with serrated edge on its outer circumference and of such diameter as to protrude outside the casing 50 through an aperture 62 in the side walls of the casing as a manual for rotatively adjusting the inner shell 54 and for holding this shell from rotating, if necessary, while rotatively adjusting the outer shell 55, which latter is given an octagonal rim formation to facilitate its being grasped for this purpose.

Within the casing 60 and partially surrounded by the shells 54 and 55 I may mount an improved form of the general type of automatic switch and time telling clock face which is the subject of my hereinbefore mentioned co-pending application Serial No. 504,532 and which I shall now particularly describe.

For closing the rear of the casing 50 I provide a plate 63 secured to the bottom and side walls of the casing and on which I may mount any form of spring motor or electric motor time keeping mechanism understood in the drawings as carried between the frame plates 3-3 and serving to impel a minute spindle I0 at the preferred speed of one revolution in one hour in a clockwise direction in Figs. 2 and 5. As is usual practice in clockwork a pinion 5 fixed to rotate with the spindle II) may mesh with the reduction gears 6 and 1 xed to rotate in unison, the latter impelling the gear 3 and thereby the hollow shaft II for the hour hand at the preferred speed of one Vrevolution in twelve hours.

Surrounding the hour shaft II is a solid fixed bushing I4 rigidly perpendicular to a slab-like base I1 of insulating material which itself is mounted on the forward plate 3 of the time movement by spacer posts 9. As the part I4 is to comprise a part of the electric circuit I choose to insert the insulating sleeve I5 between the bushing I4 and the hollow hour shaft II.

The bushing I4 is designed to afford a solid mount for all the parts of my improved time switch as well as for the clock face I3 having the hub portion 64 for solid and xed mounting upon the forward end of the bushing I4. In front of the clock face I3 I may mount a regular form of hour hand 33 upon the hollow shaft II and in front of same a regular form of minute hand I2 retained upon the forward end of the minute spindle I0 by the nut 65.

Between the insulating base I1 and the clo'ck face-I3 are the parts of my improved electric switch mechanism comprised of the settable but normally stationary insulative and conductive discs shown in Figs. 8 to 18 inclusive and the movement impelled, contact making and breaking Wiper 26. The Wiper 2 6 is iixedly carried by a hub 21 which together with the gear 28, made of insulating material, is xed to rotate with the insulative bearing sleeve 29 upon the mounting bushing I4.

The hub 21 contains a circular groove in which presses with light friction the wire brush 30 supported upon the switch base I1 in electrical contact l.with the binding post screw 36 for the line wire 39 and the insulating gear 28 being preferably of the same diameter as the hour shaft gear 8 is driven in unison therewith at the same rate of speed by a pinion 66 of the same diameter as the small reduction gear 1 and xed to the same spindle 61 which has bearing in a flxed bushing 68 in the switch base I1. It will thus be seen that the contact wiper 26 will be impelled in the same direction and at the same rate of speed as the hour hand 33 and in' insulated relation to all metallic parts so far described except the current feeding brush 30.

Suitable thrust retaining means for the rotatable structure carrying the wiper 26 may be furnished by the lock nuts 69 and 10 which may thread onto the mounting bushing I4 and be separated from all electrically alive parts of the switch rotor by a thin insulating bushing 1I.

Between the nut 10 and the clock face I3 and carried rotatively upon the hub of the latter is the assembled conductive and insulative compound disc structure shown in Figs. 8 to 18 inclusive, which structure is pressed forwardly against the back of the clock face I3 and maintained in electrical connection with the nut 10 and thereby with the mounting bushing I4 by the cupped spring washer 12. The mounting bushing I4 is therefore placed in electrical connection with the other binding post screw 34 by means of a connecter strip 35, the binding post 34 taking the load wire 39'. From the foregoing it will be plain that when the contact wiper 26 rests against the conductive disc of Fig. 9 circuit is completed between binding posts 34 and 36 and that when the wiper 26 is separated from the conductive disc of Fig. 9 by the insulative disc of Fig. 7, this circuit remains broken. The details of the conductive and insulating discs will next be described.

Referring to Figs. 7 and 8 there is shown the insulative disc 2| which may be made from any suitable nonconductive material such as fabric impregnated with baketlite or other thin tough and preferably smooth material, preferably impervious to moisture and of goed dielectric property which. I have shown split from its outer rim to its central bearing hole with an irregular form of break which among other features includes the tongue portion 13. Disc 2I also carries the projecting stud 23 preferably of insulative material by which the disc 2| may be rotatively adjusted. Figs. 9 and 10 show the corresponding conductive disc 20 likewise split in an irregular line from its periphery to its central opening and further having the stop tongue 14, the drop of! lip 24 for co-acting Awith thecontact wiper 26 to effect a quick break ofv the circuit, and having the projecting stud 22 preferably of insulative material and by which the disc 20 may be rotatively and independently adjusted.

Figs. 12, 14 and 16 show the discs 20 and 2| interlappingly assembled and given a common bearing upon the s ame retaining hub 16. When so assembled the relative movement of the two discs at one extreme is shown in Fig. l2 where the stop tongue 14/has brought up against the keywy-shaped cut-out in the insulative disc 2I. A full 36u-degree relative movement between the discs will result in the relationship of the discs tially the path indicated between two circular broken lines in Figs. 12, 14 and 16. It will be seen that at each extreme relative position of the discs the co-operative relationship of the split portions of each disc is the means which maintains their properly overlapping relationship to permit their back and forth movement relatively from each of these extreme relationships shown in Figs. 12 and 14 and that the tongue 13 plays an important part to this end.

Fig. l1 shows on a much enlarged scale the condition of four thicknesses which obtains at the cut-out portions of the discs when they are positioned at their extreme of relative movement indicated in Fig. 12, it being understood that at other points on the circle there are but two thicknesses and to compensate for this varying overall thickness as the relative adjustment of the discs is changed, I may to advantage employ a thin and slightly cupped friction washer 18 between the disc and the retaining lip of the hub 15.

Fig. 16 shows a relative adjustment of the two discs approximately midway the extreme position of Figs. l2 and 14 and if the contact wiper 26 be assumed to be pressing against these discs in its slowly impelled movement as it travels in unison with the hour hand it will be seen that at one point in its travel the wiper 26 Will drop off from the raised lip portion 24 of the conductive disc 26 onto the insulative disc 2| causing a snap break of the current owing to resiliency in one or both the contact wiper 26 or the lip 24,-the before and after positions being shown in Fig. 17. As the wiper 26 continues its travel it will come to a point where it drops smartly off from the insulative disc 2| onto the conductive disc 20 according to the before andafter positions shown in Fig. 18.

Fig. 13 shows that with the discs adjusted as in Fig. 12 the wiper 26 will drop off from the lip 24 and onto the conductive disc 20 again without contacting the insulative disc 2| and with only the nterruption of the circuit which is occasioned by the instantaneous snap of the wiper 26 as it leaves the lip 24. A practicaluse for this adjustment of the discs would arise in the use of my improved time switch as an automatic control for an electric cook stove where at such times as the time switch was not to be employed for automatic making and breaking of the current to the heating elements of the stove, no separate switch would have tobe employed to make it possible to use the stove continuously as has heretofore been necessary with time switches used for this purpose because of the fact that no means existed in the time setting instrumentalities to avoid a period where the circuit would be broken by the ltime switch. 'I

Fig. 15 shows that with the discs adjusted asin Fig. 14, the wiper 26 will drop' off from the edge of the insulative disc 2| directly onto another portion of the insulative disc 2| without ever coming into contact with the conductive disc 2li.v A prac-1 tical use for this adjustment of the discs would arise inthe use of my improved time switch in connection with the receiving of radio programs where on all occasions vexcept when' the time switch is purposely set for the function of automatically turning on the radio set at a definite hour to catch a desired program, the set would not be furnished with current through the time switch.

Fig. 16 also shows one of several means that may be used to provide a propelling engagement between the stud 22 and either of the shells 54 or 55 and between the stud 23 and the other of said shells and consisting in a idexible metallic strip 19 normally bowed to cause a notch in this strip to engage the stud 22 or 23 but capable of yielding to an arc of greater curvature more nearly in conformity with the circumference of the shell 54 or 55 so that in the assembling of the shell 55 if it has threaded engagement with the shell 54, the stud 23 will automatically seat itself in the impelling notch in the strip 19. For releasing the impelling engagement of strip 18 with the stud23 I may provide a lift pin 80 fast to the strip 19 and projecting outwardly through the shell to be grasped and pulled when it is desired to dis-assemble the parts. It is good practice to permit one end of the strip 19 to have some sliding ability relative to the shell on which the strip is mounted to accommodate its change of curvature in the assembling and dis-assembling function explained above. Of course many other forms of mechanical engagement for causing the shells 54 and 55 to lmpel the studs 22 and 23 re.- spectively may be employed.

The operation of the time switch consists merely in connecting to whatever circuit is to be put under time control and then adjusting the insulative and conductive discs so that the annular portion thereof which is visible to the user surrounding the face of the clock shall indicate by their preferably contrasting colors that period of the twelve hours of the day during which the circuit through the time switch will be made and that period during which the circuit shall remain broken. To accomplish this I arrange the tip end of the Wiper 26 which is in contact with the discs 26 and 2| to coincide in its position on the circle with the hour hand 33. 'I'hus in Fig. 2 the circuit is to be broken at quarter after three and made at half past five or vice versa depending upon what significance is assigned to the respective colors of the two discs. In manipulating the shell 55 to move the disc 2| the disc 26 may be disc 20 held from turning, the shell 55 Vwill be held from turning by the hand of the operator and thering 6I rotated by successive strokes of the operators hand against its edge. Whereas in the particular illustration there are shown no means for restricting the rotative movement of the shell 55 and the ring 6| to a contra-clockwise direction, such means would be desirable to prevent the contacting endof wiper 26 from digging into the drop off lip 24 or the edge of the insulative disc 2| which it has last passed and such means are so well known in many arts comprising ordinary pawl and ratchet wheel, oneway ball clutches, etc.,that they could be provided atY any suitable point 'without requiring invention as to mechanical detail. `One possible arrangement to prevent a clockwise rotation either of shell 55 or of the ring 6| is illustrated turning for the purpose of adjusting the time setting of discs 20 and 2|, In this modification there is substituted for the ring 8| a bell shaped shell 8| which in central section may have the shape indicated in Fig. 6 to be secured to the shell 5I by a. screw 82 of which there may be a series around the circle, the shell 8| having a bearing fit in the clock case aperture 5| and thereby serving as the mounting means for the shell 55 being retained by an auxiliary shell 83 or a series of thrust pieces rotatable in the casing recess 53 and capable of being disassembled by removing the screws 82. Fig. 6 indicates the designed method of grasping shell 54 with the finger and thumb of one hand while permitting the simultaneous grasping of shell 8| by the other hand so that the desired adjustment of the timing discs 29 and 2| can be conveniently and quickly effected. Also this modification vpossesses the advantage of eliminating any opening whatever in the sides of the casing or elsewhere that could permit the entrance of dirt or foreign particles to the impairment of the interior mechanism. In the entire structures of Figs. 1 to 6 inclusive it will be noted that all parts which can come in contact with the hands of the user as well as all metallic parts of the time mechanism or clock movement employed are carefully and thoroughly insulated from any electrically alive parts of the switching mechanism and the current may be led into and out of the time switch through the g wires 39 and 39 themselves thoroughly insulated and conveniently passing out of the casing through an insulating bushing 84 in the back plate 63, see Fig. 4.

Still another modification of the means for adjusting the time setting of the discs 20 and 2| is shown in Figa 19, 20 and 21. In these figures the shell 55 is stationary and removably mounted in the aperature 5| of the clock case. There is provided a circular retaining ring 85 of a diameter to abut against and be secured to the sides of the casing by the screws 86. Two toothed ring gears 81 and 88 are given peripherial bearing in the retaining ring 85 and retained therein by the thrust ring 89. Suitable apertures 90 in the bearing ring 85 permit entrance for 4mesh with ring gear 81 of a correspondingly toothed setting wheel 9| at the lower left side of the casing (shown at the right side in the rear View Fig. 19) and of an additional toothed setting wheel 92 to mesh with ring gear 88 and positioned at the lower right hand side of the casing (shown at the left side in the rear view of Fig. 19). Each of the setting wheels 9| and 92 project outwardly through slots in their respective sides of the casing so that they can be turned by successive strokes of the hand of the user. The setting wheel 9| is pivoted at 93 to a bracket 94 which may be secured to the side of the case and which carries the pawl or click 95 pressed by the leaf spring 96 into engagement with the teeth of the wheel 9| to permit rotation of ring gear 81 only in a contra clockwise direction viewed from the front of the time switch (clockwise direction as viewed from the rear in Fig. 19) The setting wheel 92 is pivoted at 91 to a bracket 98 which may be secured to the side of the case and which carries the pawl or click 99 pressed by the leaf spring into engagement with the teeth of the wheel 92 to permit rotation of ring gear 88 only in a contra clockwise direction viewed from the front of the time switch (clockwise direction as viewed from the rear in Fig. 19).

The ring gear 81 carries the forwardly projecting forked bracket ||l| adapted to engage the projecting stud 22 for impelling same to any desired time setting of the conductive disc 20 and the rear ring gear 88 carries the forwardly projecting forked bracket |82 to engage the projecting stud 23 for turning the insulating disc 2| to desired time setting.

It develops in practice that it is a somewhat easier and more natural way of manipulating the setting wheels 9| and 92 outside the casing to move the exposed portion of the Wheel downward rather than upward so I may interpose an idler gear 22 shown in Fig. 22 between the wheel 9| and the forward ring gear 81 to reverse the direction in which wheel 9| shall be moved for rotating the ring gear 81 in the same direction as ring gear 88 is rotated and in this modification the pawl 95' will be reversed to permit wheel 9| to turn only clockwise as viewed in Fig. 19.

Attention is called to the fact that a different form of glass Window or crystal is shown in Figs. 19 and 21 from that shown in Fig. 20 in that the crystal 56 of Fig. 20 is shown as supported in a sheet metal rim 55' much similar to the shell 55 in Fig. l but in this instance not used as a manual for effecting any time setting of the switch and therefore made merely for reasonably secure and preferably removable mounting in the aperture of the clockycase 50. Figs. 19 and 21 disclose the ability to do away with the expense and complication of the crystal holder 55 of Fig. Z0 by varying the position of the parts shown in Fig. 20 as supported upon the movement frame 3 which include the conductive and insulative discs 20 and 2| as well as the clock face and hands so that they are disposed further back in the case bringing the discs 2| and 20 into substantially the same plane as the rings 81 and 88 with accommodating change in the bent offset relationship of the forked members |0| and |02 which engage respectively the disc posts 23 and 22. This gives room for the mounting o'f a crystal of glass 56 which may be convex in nature as indicated in Fig. 21 of proper diameter to seat directly in the circular recess 53 where it may be secured by cement or removable means as desired. In this case to conceal the parts of the disc propelling mechanism which are unimportant to the visual indication of the time setting such as the disc post 23 and the forked member IUI', I may frost a suitable width circular band portion |01 of the crystal extending inward from its edge preferably exposing a sufhcient annular portion of the discs 20 and 2| circumferentially outside the clock face to afford an easily observed appearance of the setting of these two discs. One advantage of this expedient of frosting the crystal where a holding rim such as 55 is omitted is to admit to the interior parts which indicate the time setting additional light to increase their visibility as viewed from outside the casing.

Mention will now be made of further adva'ntages which the foregoing described constructions and principles of operation have been found to yield in the practical use of a time switch of this character for its usual purposes and also of modifications possible which are so simple that they will not require explicit illustration to clearly understand.

One such modification which has been illustrated resides in providing the time setting wheels 9| and 92 with knobs |04 and |05 respectively indicated by broken lines in Figs. 19 and 21 as protruding at the front of the casing and made fast to the pivot shaft 91 which extends both insidel and outside the front wall of the casing and to which the gear 9|' or 92 is pinned or keyed to turn inunison therewith, this same modification being possible to the pivot shaft 93. Manuals in the form of knobs |04 and |05 would be useful not only in the case of housing my improved time switch in a portable clock like case such as 50 shown herein but would be particularly desirable if in place of such case the time switch mechanism were contained Within the relatively large cabinet of a radio set to expose only the clock face and hands and switch setting discs through an-open ing in the front wall of the cabinet. vObviously to provide manuals such as the wheels 9| and 92 would require a projection of the housing to afford side portions from which wheels 9| and 92 could protrude but this becomes unnecessary if knobs such as |04 and |05 are emp1oyed, or I might in some instances prefer to use one knob such as |04 or |05 and one wheel such as 9| or 92 depending upon the circumstances of the desired shape and disposition of the housing.

Referring to the contact wiper 26 I prefer to give the terminus of same which wipes against the discs a somewhat pointed or rounded formation to assure its quick and unhesitating drop oif from one disc onto the other however slowly it may be rotated in the course of reaching its drop off point. I may aid the facility withl which the wheels 9| and 92 may be turn-ed by the hands of the user by shaping them near their periphery with a series of circularly arranged protuber@ ances or depressions for better grasp by the iiesh of the fingers and protection of the hand against any sharpness or roughness that gear teeth such as those shown might possess. I may also avoid any direct contact of the hand of the userwith the wheels 9| and 92 by arranging a pivoted lever to work up and down having a pawl or any suitable one waydrive means for advancing the wheels 9| or 92 in desired stanges of movement. By making the relationship of the teeth on wheels 9| and 92 to the teeth on rings 81 and 88 after the nature of bevelgears or their equivalent I may' provide knobs such as |04 and |05 whose pivot such as 91 will extend laterally through the side walls of the case instead of forwardly through the front, or I may have` one such knob extend through the front and one through the side.

I do not limit these improvements to the use of the disc 20 as -an electrical conductor or circuit controlling track for a wiper such as 26 but may employ the discs 20 and 2| and the means of their relative setting here disclosed for determining the times of automatic switch action in other ways. ff

Should it be desired to use my improved time V switch under circumstances where the face of the clock cannot be visible any of the outside manuals disclosed or suggested herein such as shells 55 and 8|, or the large disc 6|, or the wheels 9| and 92, or knobs |04 and |05, may

carry time indicating graduation's or be assov ciated with'such graduations carried on the casing or elsewhere to indicate without reference to the clock face the times at which the discs 20' pointed out that owing lto the length and to the exibility of wiper 26 and to the uplifting tendency of the edges of the two discs when they are assembled which will be somewhat plain from Figs. 8 and 10 but which is well lillustrated 'in Fig. 17 and which in practice is found to be substantially greater than the theoretical alignment of these edges disclosed in Figs. 13, 15 and 18, the contacting point of wiper 26 seeks and vis able to enter a small space under the edge of either disc it has last dropped off from and can continue to enter and occupy a space between two adjacent surfaces of the discs slightly separating them to an even greater extent to accom-g modate its presence, and without permanent impairment of the shape or condition of any of the operating parts concerned. Obviously there would come a limit to the amount the wiper 26 could thus effect its entrance between the discs but this amount is a substantial degree amounting to a. possible one eighth of a circle so it is not necessary for the protection of my improved mechanismthat any pawls or clicks employed to prevent retrogressive movement, such as pawls 95, 95' or 99 work to this effect on steps representing such a small increment of a circle as do the teeth on the wheels 9| and 92 but may instead work upon a ratchet wheel fixed to turn with wheels 9| and 92 and having, say, only eight teeth or' notches for the pawls to engage with. This would in fact be a convenience to a user unfamiliar with the setting of the device because it would give him this much more allowable retrogressive movement if in attempting to make a desired setting he should accidentally turn the disc past the intended graduation since he could easily turn it backward the small amount which would be likely to constitute his error instead of being forced'to advance the disc all the way around the circle again to reach the desired graduation.

Many modifications other than those here shown will suggest themselves to workers in this art and the following claims` are drawn to the principlesi of4 construction and operation of which the particular device here disclosed is but illustrative, and the claims are intended to cover all fair equivalents or modified forms for seizing upon these principles which fall within the scope of the basic ideas here disclosed.

What is claimed is,

1: In atime setting device, a plurality of circular members each comprising a ring of complete but not overlapping circular extent and containing a break extending inwardly from its peripherial edge and through which break the other member is adapted to enter and slide back and forth with a circular movement t'o the extent of a full relative turn of each member rela'- tive to the other member, the disposition of said two breaks being so different that said breaks can not be coniiguratively aligned whereby the complete withdrawal of one member from the break in the other member is prevented unless more thana full turn of relative movement between said members takes place.

2. Time setting means for a casing enclosed timing device, including in combination with the casing, a time setting means protruding from a front wall of the casing for manipulation by one hand of the user, and another time setting means co-operating with said first means and designed for simultaneous manipulation therewith by the otherl hand of the user and extending from a. lateral wall of the casing to avoid interference by one hand of the user with the other hand of the user when said means are simultaneously manipulated.

3. Time setting means for a casing-enclosed timing device, including in combination with the casing, a time setting means connected to operate said timing device, and a manual for selectively adjusting said means and comprising a wheel of sumciently large diameter to extend across and protrude from both and opposite sides of said casing.

'4. In an on and olf time switch, a ,clock face with hands to tell the time of day, an enclosing case having a window to expose said clock face, a transparent cover to close said window, a rim carrying said cover and swivelled to rotate in said window opening, switch contacts, and connections whereby turning said rim readjusts the operating position of said contacts to determine the' time at which the current shall be made and broken therethrough.

5. In an on and oil time switch, a clock face with'hands to'tell the time of day, an enclosing case having a'window opening to expose the clock face, a transparent cover to close said opening, two rims swivelled to rotate in said opening one of said rims carrying said cover, two circuit controlling elements variable as to their relative and absolute positions for determining the times of switch action, and connections whereby yeach of said rims adjusts respectively the time set position of each of said elements.

6. In a combined clock and time switch, a vclock face. with hands to tell the time of day, an enclosing case having a window suficiently large to expose not only said clock face `but alsoan annular space of substantial width surrounding the same, two interlapping discs rotatively adjustable about a pivot concentric with said clock face and of greater diameter. than said clock face to be visible in the said annular space when viewed from outside said case, circuit controlling means with connections rendering said means adjustable by said discs as to their time setting, and means operable outside said case for moving said discs to a desired time setting position.

7. In a combined clock and time switch, a clock face with hands to tell the time of day, an enclosing case having a window suiliciently large to expose not only Ysaid clock face but also an annular space of substantial width surrounding the same, indicating means appearing in said annular space to inform the operator as to the setting of said time switch, and a transparent cover closing said window and havingl a translucent ring portionoi less width than the said annular space to conceal a portion of said indicating means while admitting light to better illuminate that portion of said means which is visible through the transparent portion of said cover.

' 8. In a settable time switch, a scale of circu- .larly arranged time graduations, a split ring of insulative material having a front face visible in register with said graduations, a split ring of conductive material having a front face visible in register with said graduations, means to mount said rings so that one ring may flex to a helical form and so that each ring may be rotated through the split portion of the other ring thereby to dispose varying extents of its circular length on respectively diierent sides of the other ring, and arotatable electric contact ymounted to wipe against the rear faces of said rings for controlling an electric circuit.

9. In a settable time switch, minute and hours hands to tell' the time of day, a clock face to be swept by said hands and carrying time-of-day graduations proximate its edge, a split ring of insulative material having a front face visible in register with said graduations, a split ring of conductive material having a front face also visible in register with said graduations, means to mount said rings so that one ring may ilex to a helical form and so that each ring may be rotated through the split portion of the other ring thereby to dispose varying extents of its circular length on respectively different sides of the other ring, and a rotatable electric contact mounted to wipe against the rear vfaces of said rings for controlling an electric circuit.

10. In a time switch in combination, an electric contact wiper, an insulative dischaving a ratchet like step to be circularly traversed by said wiper, a conductive disc having a ratchet like step to be circularly traversed by said wiper, means permitting the relative circular adjustment of said two discs to vary the respective portions of each disc which shall be contacted by said wiper, means for manually adjusting the relative and absolute rotative positions of said discs, and means to prevent theretrogressive movement of said discs to prevent damage to the switch through attempted movement of said contact steps past said wiper in the wrongidrection.

1l. In a settable time switch, a scale of circularly arranged graduations, a split ring of substantially 360 degrees extent and of ilexible material to be separable at its split portion, a second split ring of substantially 360 degrees extent and also of flexible material to be separable at its split portion, a hub to `cai-ry and retain both of said rings so that each ring may pass through the split portion of the other ring and be rotatively adjustable upon said hub through substantially 360 degrees relative to the other ring, means to maintain the separated disposition of the split portion of each ring to prevent loss of entrance for either ring to the split portion of the other ring, and means to mount said hub for free rotative adjustment through any desired number of turns for determining the absolute circular positioning of said rings.

12. In an on and oi time switch, a clock face with hands to tell the time of day, an enclosing case having a window to expose said clock face, a transparent cover to close said window, switch contacts, and ring members larger in diameter than said clock face, and connections whereby turning said ring members re-adjusts the operating position 'of said contacts to determine the time at which the current shall be made and broken therethrough.

13. In a time switch in combination, an'electric contact wiper, an insulative disc having a ratchetlike step to be circularly traversed by said wiper, a conductive disc having a ratchet-like step to be circularly traversed by said wiper, a rotatable member separately mounted for detachable engagement with each' of said discs to effect their circular adjustment, and gears for separately adjusting the relative and absolute rotative positioning of each of said discs by action upon said member, said gears having means to prevent the retrogressive movement of themselves and thereby of said discs to prevent damage to said ratchet like steps of the discs.

14. In an on and off time switch, a`clock face with hands to tell the time of day, an enclosing case having a window to expose'said clock face, a

-transparent cover to close said window, switch contacts, and ring members larger in diameter than said window with toother outer peripheries, connections whereby turning said ring members .re-adjusts the operating position of said contacts to determine the time at which the current shall be made and broken through said contacts, and gears disposed to be invisible in said window and meshing with said toothed ring members for Inanually operating the same.

15. In timing mechanism, in combination, a clock works, a frame plate to support said clock works, a bearing bushing rigid with said frame plate and extending forwardly from the plane of said clock works,a clock face supported rigidly at the forward end of said bushing and centered thereon, a spindle driven by said clock works and extending forwardly through said bearing bushing, a clock hand carried by said spindle to sweep in front of said clock face, and circuit switching means including a circuit controlling rotor rotatable about said bearing bushing back of the clock face, interconnected gears on respectively opposite sides of said frame plate comprising means whereby said clock works impels said rotor, and discs to determine the time said rotor shall act to switch a current, rotatively adjustable about said bearing bushing also in back of said clock face, in which arrangement said discs but not said rotor are visible outside the area occupied by Said clock face when said timing mechanism is viewed from the front.

RAYMOND D. SMITH.

Cil 

